A Becton Dickinson LSR Fortessa flow cytometer analyzer is being requested by investigators at Purdue University's university-wide and Cancer Center Shared Facility to replace a 12-year-old Beckman-Coulter FC500 and to provide easy porting of sorting experiments to our existing FACS Aria III cell sorter. Since many of our users are outgrowing the technical capabilities of the FC500 they are increasingly performing analysis- only experiments on the FACS Aria III cell sorter leading to scheduling problems. As described in the proposal we also have a major new Drug Discovery Center coming online in spring, 2014. With over 100 members, many of whom will need to test drug targeting and drug effects on single cells, we expect a big increase in new users during 2014. The new instrument will be used by 12 Major Users with 17 funded NIH funded grants and 4 Minor Users with 2 funded NIH grants. Of the estimated 80 percent use by Major Users, 75 percent is NIH- funded. Minor Users have an estimated 20 percent use and this includes 2 NIH funded grants with an estimated 5 percent use. Therefore a total of 80 percent estimated use by NIH grantees is anticipated. We have a demonstrated and continuing strong institutional commitment of our facility as evidenced by the University's purchase of the FACS Aria III sorter and the multi-year support of instrument maintenance contracts and salary of our technical staff. The new instrument will be placed within an existing facility with existing, well-functioning Management Structure and Advisory Committees already in place. While we are already very comfortable and experienced in running advanced multicolor experiments for analysis on our 5-laser 14-color FACS Aria, the popularity of this instrument is becoming a problem in terms of scheduling both analysis-only and sort experiments. For this reason we have chosen a 5-laser BD Fortessa configuration with similar lasers and fluorescence collection optics to allow for easy porting of analysis experiments to the Aria sorter and to greatly expand the number, scope and complexity of analysis-only experiments for our users who would now be able to use the new requested Fortessa instrument. The combination of existing and new instrumentation would allow us great flexibility in meeting the needs of our users. Similar lasers and fluorescence collection optics will also help us to more easily train our users and get them thinking about proper matches of laser excitations with probes of interest that could be used on either instrument. In summary, this combination of existing instrumentation with the requested instrument should allow us to make optimal total throughput of experiments and training for our users in the greater Purdue community.